# @Author: Eric Ito
# @Date: 1/26/2009
# @Name: Project Euler Problem 16

"""
215 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26.

What is the sum of the digits of the number 2^1000?
"""

def main():
    sum = 0
    for d in str(2**1000):
        sum += int(d)
    print sum
if __name__ == "__main__":
    main()
